Solenoid assembly

ABSTRACT

A solenoid assembly for use in connection with a housing and valve body is provided. The assembly includes a magnetic coil, a magnetic pole piece, an operating rod, and a magnetic armature. The operating rod is slidably disposed within a portion of the pole piece and is at least in part centered relative to the pole piece. Activation of the coil provides an attraction between the armature and the pole piece. An embodiment of the assembly may additionally include one or more bearings positioned between the operating rod and the pole piece.

TECHNICAL FIELD

The present invention relates to magnetic solenoids, including anassembly for a magnetic solenoid configured for use in connection with asolenoid operated valve.

BACKGROUND

Magnetic solenoid valves are subject to tolerance “stack up” associatedwith the inclusion of multiple components. To improve quality andfunctionality of solenoid assemblies, including the function of anoperating rod, there is commonly a desire to reduce the stack up ofassociated dimensional tolerances. A reduction in tolerance stack-upcan, among other things, improve the alignment associated with operativecomponents of the assembly.

SUMMARY

A solenoid assembly for use in connection with a housing and valve bodyis disclosed. The assembly includes a magnetic coil, a magnetic polepiece, an operating rod, and a magnetic armature. The operating rod isslidably disposed within a portion of the pole piece and is at least inpart centered relative to the pole piece. Activation of the coilprovides an attraction between the armature and the pole piece. Anembodiment of the assembly may additionally include one or more bearingspositioned between the operating rod and the pole piece.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example,with reference to the accompanying drawings, wherein:

FIG. 1 is a cross-sectional view of an assembly for a magnetic solenoidaccording to an embodiment of the invention;

FIG. 2 is a cross-sectional view of an assembly for a magnetic solenoidaccording to another embodiment of the invention; and

FIG. 3 is a cross-sectional view of an assembly for a magnetic solenoidaccording to a further embodiment of the invention.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments of the presentinvention, examples of which are described herein and illustrated in theaccompanying drawings. While the invention will be described inconjunction with embodiments, it will be understood that they are notintended to limit the invention to these embodiments. On the contrary,the invention is intended to cover alternatives, modifications andequivalents, which may be included within the spirit and scope of theinvention as defined by the appended claims.

An embodiment of a solenoid assembly 10 is shown in FIG. 1. In theillustrated embodiment, the solenoid assembly 10 is shown as part of alarger valve assembly. The illustrated solenoid assembly 10 includes acoil 12, a pole piece 14, an operating rod 16, and an armature 18. Acenterline for the assembly is generally designated as CL. A portion ofa valve body is generally designated as element 20. However, one ofskill in the art will recognize that the invention is not limited to avalve body 20 of the type shown, and other forms and configurations ofvalve bodies may be employed without departing from the teachings of theinvention.

The coil 12, pole piece 14 and armature 18 are each configured to be atleast partially magnetic, and those components may be referred to as“magnetic.” In an embodiment, the operating rod 16, which is sometimesreferred to as a pin or operating pin, is not comprised of a magneticmaterial and, hence, may be referred to as a “non-magnetic” operatingrod. For example, without limitation, the operating rod 16 may becomprised of stainless steel, aluminum, or brass. The illustratedsolenoid assembly 10 may also be referred to as a magnetic solenoid ormagnetic solenoid assembly.

At least a portion of pole piece 14 is positioned inside of coil 12. Inthe illustrated embodiment, a majority of the pole piece that extend inthe direction parallel to the centerline CL of the assembly ispositioned inside of coil 12.

In an embodiment of the invention, a pin or operating rod 16 ispositioned within a portion of a cavity or opening (such as a bore)formed by an inner surface of pole piece 14. Rod 16 can be configured togenerally extend longitudinally about the centerline CL of the assembly10. As shown, armature 18 is positioned about an end of operating rod 16that is more remote from an end configured to communicate with a valvebody 20.

In an embodiment, operating rod 16 is slidably disposed within a portionof pole piece 14, and extends beyond coil 12 and pole piece 14. Theoperating rod 16 can then, as generally illustrated, further extend intoa receiving portion of armature 18. The receiving portion of armature 18may comprise a cavity or aperture formed in a portion of the armaturepositioned about centerline CL. Armature 18, which can be centeredrelative to pole piece 14, may also serve to keep the operating rod on adesired (e.g., “on-center” or centerline) path with respect to othercomponents of the assembly 10. In an embodiment of the invention, theactivation of coil 12 can provide an attraction between armature 18 andpole piece 14. For example, such an activation can attract the armature18 to pole piece 14. However, as generally illustrated in FIG. 1, theassembly 10 may be configured such that, in at least one operativestate, coil 12 does not surround armature 18.

As generally illustrated, armature 18 can be configured to interactdirectly with a portion of housing 22. That is, the assembly 10 can beconfigured such that at least a portion of an associated flux travelsfrom the pole piece 14, into and through the armature 18, and directlyon to a portion of an associated housing 22.

For some applications, such a configuration can eliminate the need forthe assembly to include a flux collector—which can reduce the number ofnecessary components associated with the solenoid assembly. A reductionin the number of components can potentially provide advantages,including a potential reduction in the “stack up” of dimensionaltolerances associated with various components of the solenoid assembly.For example, because the invention does not require a conventional fluxcollector, the costs for components may be reduced and the tolerancestack up of the assembly, for example in the direction perpendicular tothe centerline CL, can potentially also be reduced.

Moreover, for some applications, the improved “packaging” of theinventive assembly (e.g., potential elimination of flux collector and/orreduction in tolerance stack-up) can permit an armature to be designedto be larger, which can potentially provide for more functionalinteraction between the armature and other components.

Another embodiment of the invention is generally illustrated in FIG. 2,where similar components discussed in connection with the embodimentshown in FIG. 1 have been designated with similar reference numerals. Asdiscussed in connection with the prior embodiment, the armature 18 maydirectly interact with a portion of housing 22; however, the assembly 10shown in FIG. 2 includes a bearing, and for most embodiments, aplurality of bearings, e.g., 24 a, 24 b. In the illustrated embodiment,the bearings are positioned between a portion of the pole piece 14 and aportion of the operating rod 16. For example, without limitation,portions of the inner surface of pole piece 14 may be designed orconfigured to retain or “seat” one or more bearings for operativecommunication with an operating rod 16. Moreover, the bearings may bepressed into the pole piece 14 from opposing ends. Further, as generallyillustrated a spring element, e.g., spring 26, may be adapted foroperative connection with the operating rod 16. In the embodimentillustrated in FIG. 2, spring 26 is positioned about the end of theoperating rod about armature 18.

In an embodiment of the invention, assembly 10 includes at least twobearings. In the illustrated embodiment, one bearing 24 a is positionedabout a first longitudinal half of the operating rod 16, which in thiscase is the half adjacent the armature 18. A second bearing 24 b ispositioned about a second longitudinal half of the operating rod 16,which in the illustrated example is positioned closer to valve body 20.The sizing, position and spacing of the associated plurality of bearingscan be configured such that the operational rod 16 slides on thebearings 24 a,24 b, which keep the armature 18 substantially centeredrelative to the pole piece 14.

Yet another embodiment of the invention is generally illustrated in FIG.3, in which similar components discussed in connection with theembodiments shown in FIGS. 1 and 2 have been designated with similarreference numerals. In this embodiment, the valve body 20 is located onthe other end of the solenoid assembly 10 when compared to theassemblies shown in FIGS. 1 and 2. For such an alternativeconfiguration, the valve body 20 is located on the same end as armature18.

The embodiment depicted in FIG. 3 is shown without the inclusion ofbearings; however, one skilled in the art will understand that bearings,for example, as generally disclosed in connection with the embodimentshown in FIG. 2, may be optionally included. Further, as generallyillustrated a spring element, e.g., spring 26, may be adapted foroperative connection with the operating rod 16. In the embodimentillustrated in FIG. 3, spring 26 is positioned about the end of theoperating rod remote from armature 18.

The foregoing descriptions of specific embodiments of the presentinvention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and various modifications andvariations are possible in light of the above teaching. The embodimentswere chosen and described in order to explain the principles of theinvention and its practical application, to thereby enable othersskilled in the art to utilize the invention and various embodiments withvarious modifications as are suited to the particular use contemplated.It is intended that the scope of the invention be defined by the claimsappended hereto and their equivalents.

1. A solenoid assembly for use in connection with a housing and valvebody, the assembly comprising: a magnetic coil; a magnetic pole piece,at least a portion of the pole piece positioned inside of the coil; anoperating rod positioned within a portion of a cavity or aperture formedby the pole piece; and a magnetic armature positioned about an end ofthe operating rod, the armature configured to interact directly withsaid housing; wherein the operating rod is slidably disposed within aportion of the pole piece, the armature is at least in part centeredrelative to the pole piece, and activation of the coil provides anattraction between the armature and the pole piece.
 2. The assembly ofclaim 1, wherein the magnetic armature is positioned about an end of theoperating rod that is more remote from said valve body.
 3. The assemblyof claim 1, wherein the magnetic armature is positioned about an end ofthe operating rod that is closer to said valve body.
 4. The assembly ofclaim 1, including a spring element positioned about an end of theoperating rod nearest the armature.
 5. The assembly of claim 1,including a spring element positioned about an end of the operating rodthat is more remote from the armature.
 6. The assembly of claim 1,wherein the operating rod is comprised of non-magnetic material.
 7. Theassembly of claim 6, wherein the operating rod is comprised of stainlesssteel, aluminum, or brass.
 8. The assembly of claim 1, wherein theoperating rod is retained on-center by the pole piece.
 9. The assemblyof claim 1, wherein at least a portion of an associated flux travelsfrom the pole piece, into and through the armature, and directly on tosaid housing.
 10. The assembly of claim 1, wherein the activation of thecoil attracts the armature to the pole piece.
 11. The assembly of claim1, wherein an associated dimensional tolerance stack-up for the assemblyconsists solely of the tolerances associated with the coil, pole piece,operating rod, and armature.
 12. The assembly of claim 1, wherein themajority of the external surface of the operating rod is in operativecontact with an internal surface of the pole piece.
 13. The assembly ofclaim 1, wherein, when the coil is in a non-activated condition, thecoil does not surround the armature.
 14. A solenoid assembly for use inconnection with a housing, the assembly comprising: a magnetic coil; amagnetic pole piece, at least a portion of the pole piece positionedinside the coil; an operating rod positioned within a portion of acavity or aperture formed by the magnetic pole piece; a magneticarmature positioned about one end of the operating rod, the armatureconfigured to interact directly with said housing; and at least onebearing positioned between a portion of the pole piece and a portion ofthe operating rod; wherein the operating rod is slidably disposed on thebearings, the armature is at least in part centered relative to the polepiece, and activation of the coil provides an attraction between thearmature and the pole piece.
 15. The assembly of claim 14, including aspring element positioned about an end of the operating rod nearest thearmature.
 16. The assembly of claim 14, including a spring elementpositioned about an end of the operating rod that is more remote fromthe armature.
 17. The assembly of claim 14, wherein a first bearing ispositioned about a first longitudinal half of the operating rod, and asecond bearing is positioned about a second longitudinal half of theoperating rod.
 18. The assembly of claim 14, wherein the operating rodis comprised of non-magnetic material.
 19. The assembly of claim 14,wherein the operating rod is comprised of stainless steel, aluminum, orbrass.
 20. The assembly of claim 14, wherein the operating rod isretained on-center by the at least one bearing.
 21. The assembly ofclaim 17, wherein the operating rod is retained on-center by the firstbearing and the second bearing.
 22. The assembly of claim 14, wherein atleast a portion of an associated flux travels from the pole piece, intoand through the armature, and directly on to said housing.
 23. Theassembly of claim 14, wherein the activation of the coil attracts thearmature to the pole piece.
 24. The assembly of claim 14, wherein anassociated dimensional tolerance stack-up for the assembly consists ofthe tolerances associated with the coil, pole piece, operating rod,bearings, and armature.
 25. The assembly of claim 14, wherein themajority of the external surface of the operating rod is in operativecontact with a surface associated with the at least one bearing and aninternal surface of the pole piece.
 26. The assembly of claim 14,wherein, when the coil is in a non-activated condition, the coil doesnot surround the armature.
 27. A solenoid assembly for use in connectionwith a housing, the assembly comprising: a magnetic coil; a magneticpole piece, at least a portion of the pole piece positioned inside thecoil; an operating rod comprised of a non-magnetic material that ispositioned within a portion of a cavity or aperture formed by themagnetic pole piece; a magnetic armature positioned about one end of theoperating rod, the armature configured to interact directly with saidhousing; and at least one bearing positioned between a portion of thepole piece and a portion of the operating rod; wherein the operating rodis slidably disposed on the bearings; the armature is at least in partcentered relative to the pole piece; activation of the coil provides anattraction between the armature and the pole piece; the operating rod isretained on-center by the at least one bearing; and the activation ofthe coil attracts the armature to the pole piece.
 28. The assembly ofclaim 27, wherein, when the coil is in a non-activated condition, thecoil does not surround the armature.